Use of aspirin, but not other NSAIDs, linked to reduced risk of leukemia

Regular use of aspirin at least twice a week is associated with a 55% reduction in the risk of adult leukemia, according to a report published in the June 13th issue of Cancer Epidemiology. Use of other NSAIDS, however, may actually increase this risk.

Several reports have linked treatment with aspirin and other NSAIDS with a reduced risk of solid tumors, such as colon, lung, and breast cancers. The current research, however, is the first prospective study to look at the effect of NSAID use on leukemia risk.The findings are based on a study of more than 28,000 postmenopausal women who were enrolled in the Iowa Women’s Health Study (IWHS), which began in 1985. As part of the study, the subjects answered detailed questions about the use of aspirin and other NSAIDS.From 1993 to 2000, 81 incident leukemia cases were recorded in the study cohort, senior author Dr. Julie A. Ross, from the University of Minnesota in Minneapolis, and colleagues note.Compared with aspirin non-users, the relative risk for developing leukemia among women who used the drug at least twice a week was 0.45, the researchers found. In terms of cancer subtypes, such use was tied to relative risks of 0.30 and 0.38 for acute myeloid (AML) and chronic lymphocytic leukemia (CLL), respectively.Regular non-aspirin NSAID use was associated with a relative risk of 1.31 for leukemia compared with non-use. The figures for AML and CLL were 1.56 and 1.09, respectively.”One of the benefits of the IWHS was that participants were specifically asked about aspirin use versus use of other NSAIDs,” Dr. Ross told Reuters Health. “So we were able to tease out the effects of each. In previous studies, they have sometimes been grouped together.”While aspirin use was tied a reduced risk of leukemia, Dr. Ross said, “I’m reluctant to make too much out of the increased risk associated with use of other NSAIDs,” because of small patient numbers. “Still, it is interesting that we saw this differential pattern and this warrants further study.”Additional studies are also needed to investigate how aspirin reduces the risk of leukemia, Dr. Ross commented. One possibility is that “by reducing platelet aggregation this reduces levels of circulating growth factors that induce cell proliferation.” (Source: Cancer Epidemiol 2003;12:000-000: Reuters Health: Anthony J. Brown, MD: June 17, 2003: Oncolink)